/*
 * Copyright (c) 2014 pkzd/1.0, 颜文泽(robin)
 * All rights reserved.
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *     1 Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     2 Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include	<asm.h>
#include	<prf.h>
#include	<time.h>

time_t	stime;

int
time_init(void)
{
	struct time tm;

	tm.t_sec = rtc_read(0);
	tm.t_min = rtc_read(2);
	tm.t_hour = rtc_read(4) - 8;
	tm.t_mday = rtc_read(7);
	tm.t_mon = rtc_read(8) - 1;
	tm.t_year = rtc_read(9);
	stime = mktime(&tm);
	return 0;
}

time_t
mktime(struct time *atp)
{
        struct time *tp;
        int s, m, h, d, mon, y;

        if(!(tp = atp))
                return -1;
	if((y = tp->t_year) < 70)
		y += 100;
	y += 1900;
        s = tp->t_sec;
        m = tp->t_min;
        h = tp->t_hour;
        d = tp->t_mday;
        mon = tp->t_mon + 1;
        if((mon -= 2) < 0){
                y -= 1;
                mon += 12;
        }
        return (((y*365 + y/4 - y/100 + y/400 + 367*mon/12 + d - 719499) * 24 + h) * 60 + m) * 60 + s;
}

time_t
time(time_t *tp)
{
	if(tp)
		*tp = stime;
	return stime;
}
